The invention relates to a medical or dental-medical treatment instrument and more particularly to a medical or dental-medical treatment instrument including a media line and an exchangeable filter.
For the kinds of treatment instruments under consideration, the structural size is restricted, in order to be able also to treat confined parts of the body, such as is the case for example in the mouth of the human body. As a consequence, media lines running in the treatment instrument are also to be formed with a cross-sectional dimension which is as small as possible. This applies also for at least one media line extending in the treatment instrument from the rear forwardly. For this reason, the media line of a treatment instrument of the kind under consideration tends to suffer a blockage in the case of contamination. This applies also if there is present in the media line a reduction of cross-section, for example in the form of a nozzle. In order to avoid such blockages it has been proposed to arrange a filter element removably in the media channel, which element can be exchanged after a certain operating time.
In U.S. Pat. No. 5,971,757 A a disc-shaped filter element is arranged in a media line between two axial parts of a treatment instrument arranged one after another.
U.S. Pat. No. 5,556,279 A shows a so-called filter cartridge for a treatment instrument of the kind under consideration, having a filter housing which is mounted between two media line sections and in which a disinfectant material is arranged between two disc-shaped filter elements, the medium flowing axially through this filter packet.
From DE 39 06 063 C2 there can be seen a dental handpiece having a filter cartridge in a water line, the handpiece consisting of three handpiece sections arranged axially one after another and the filter cartridge being arranged in the middle handpiece section.
With the configuration in accordance with the invention the filter element has the form of a sleeve, the direction of passage of the medium through the filter element being directed transversely to the sleeve wall. With this configuration a large through-flow area is available for the medium, so that the flow resistance is relatively small. By means of the sleeve form of the filter element, a small cross-sectional size is provided which allows itself to be advantageously integrated also in the restricted space relationships of a treatment instrument of the kind under consideration.
These advantages apply also for a filter cartridge and for a handpiece for a treatment instrument in accordance with the invention.
Further, with a treatment instrument formed in accordance with the invention there is provided an arrangement for mounting and dis-mounting, of the filter cartridge.
Further in accordance with the invention there is arranged in a forward handpiece part and/or an insert part which can be at least partially placed therein from the rear, a free space the lateral opening of which is covered over by means of a connecting sleeve mounted from the rear and with a retracted connecting sleeve is open, whereby a filter cartridge which can be mounted in the media line can be put in place in the free space, and again removed, through the opening. This configuration makes possible an arrangement of the filter cartridge which on the one hand is arranged internally protected from contamination and damage and on the other hand is easily accessible, for example for the purpose of cleaning or exchange.
Further developments of the solutions in accordance with the invention make possible a simple and rapid connection or release of the filter cartridge to or from associated media line sections. For this purpose, plug-in connections are preferably suited, which by means of an axial displacement of the filter cartridge and an insert part can be readily and rapidly mounted or released.
According to additional embodiments of the invention there are provided features which improve the filter cartridge both with regard to its construction and also filter characteristics and stability, and make possible a simple construction of small cross-sectional size and also an economical construction.